Featured Research

from universities, journals, and other organizations

Evolutionary history of a cancer-related gene

Date:
June 6, 2013
Source:
Centro Nacional de Investigaciones Oncologicas (CNIO)
Summary:
Scientists have described how a genetic duplication that took place in the vertebrate ancestor some 500 million years ago encouraged the evolution of the ASF1b gene; a gene essential for proper cell division and related to some types of cancer such as breast cancer.

This is a phylogenetic tree showing the moment at which the duplication of the original gene in the vertebrate ancestor (x2) took place, as well as the evolution of the resulting duplicate genes: ASF1a (above) and the gene that is related to cancer, ASF1b (below). The areas marked in green indicate positions that have mutated in each of the lineages.
Credit: CNIO

How and when evolution generates diversity or gives form to proteins, living beings' functional building blocks, are essential questions that still surround the theory of evolution. In humans, the majority of genes have emerged via genetic duplication, a strategy in which a gene generates two identical copies that can evolve to generate different proteins.

A study published today by scientists from the Spanish National Cancer Research Centre (CNIO) describes how a genetic duplication that took place in the vertebrate ancestor some 500 million years ago encouraged the evolution of the ASF1b gene; a gene essential for proper cell division and related to some types of cancer such as breast cancer. The results of the study are published in Molecular Biology and Evolution.

The conclusions of the study are the result of collaboration between the team led by Alfonso Valencia, Vice-Director of Basic Research and Director of CNIO's Structural Biology & Biocomputing Programme, and the team led by Genevieve Almouzni, a member of CNIO's Scientific Advisory Committee, at the Institut Curie in Paris, France.

Valencia says that: "When proteins have such a close similarity as the one that exists between the two human copies of the ASF1 gene -- ASF1a and ASF1b -- it is commonly assumed that they have similar functions in cells; in this case related to fundamental processes such as DNA remodelling and repair, cell division, cell proliferation and genetic transcription or activation."

The Genomic Environment, Key to Success in Separating Functions

Almouzni's team discovered several years ago that, despite the similarity in structure, the two copies of ASF1 were not redundant, but rather had divided up their ancestral functions. How and why, though, did this specialisation happen, and what biological advantages were conferred on the cells?

The authors of the study have used sophisticated ancestral state reconstruction methods in order to track the evolutionary history of ASF1 from its duplication. To this end, they have studied the genome of up to 40 species, some of them as diverse as sea urchins, lampreys, fish, frogs or a wide spectrum of mammals and birds.

Federico Abascal, first author of the study, explains that: "Our results suggest that ASF1b is the original copy that was duplicated millions of years ago. Following the duplication, the other copy moved twice within the genome, settling in very different surroundings to the original." Daniel Rico, one of the study's authors, adds that: "It is precisely this localisation of the two genetic duplicates in such different genomic environments that possibly opened up the door for ASF1b and ASF1a to follow different paths."

According to the researchers, the new genomic context and positive selection are responsible for the subtle differences between the two proteins, which are those that allow them to develop different functions.

"This function separation process put an end to the adaptive conflict in the ancestral gene, which should have simultaneously carried out very different competitive functions that were indispensable for the cells," says Valencia.

The researchers point out that studying the molecular history of genes is fundamental to understanding how they adapt to the functions they develop. In the case of proteins as important as ASF1, this knowledge is crucial for establishing the process of its deregulation in cancer.


Story Source:

The above story is based on materials provided by Centro Nacional de Investigaciones Oncologicas (CNIO). Note: Materials may be edited for content and length.


Journal Reference:

  1. F. Abascal, A. Corpet, Z. A. Gurard-Levin, D. Juan, F. Ochsenbein, D. Rico, A. Valencia, G. Almouzni. Subfunctionalization via adaptive evolution influenced by genomic context: the case of histone chaperones ASF1a and ASF1b. Molecular Biology and Evolution, 2013; DOI: 10.1093/molbev/mst086

Cite This Page:

Centro Nacional de Investigaciones Oncologicas (CNIO). "Evolutionary history of a cancer-related gene." ScienceDaily. ScienceDaily, 6 June 2013. <www.sciencedaily.com/releases/2013/06/130606101726.htm>.
Centro Nacional de Investigaciones Oncologicas (CNIO). (2013, June 6). Evolutionary history of a cancer-related gene. ScienceDaily. Retrieved September 22, 2014 from www.sciencedaily.com/releases/2013/06/130606101726.htm
Centro Nacional de Investigaciones Oncologicas (CNIO). "Evolutionary history of a cancer-related gene." ScienceDaily. www.sciencedaily.com/releases/2013/06/130606101726.htm (accessed September 22, 2014).

Share This



More Health & Medicine News

Monday, September 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Liberia Pleads for Help to Fight Ebola

Liberia Pleads for Help to Fight Ebola

AP (Sep. 22, 2014) Liberia's finance minister is urging the international community to quickly follow through on pledges of cash to battle Ebola. Bodies are piling up in the capital Monrovia as the nation awaits more help. (Sept. 22) Video provided by AP
Powered by NewsLook.com
Global Ebola Aid Increasing But Critics Say It's Late

Global Ebola Aid Increasing But Critics Say It's Late

Newsy (Sep. 21, 2014) More than 100 tons of medical supplies were sent to West Africa on Saturday, but aid workers say the global response is still sluggish. Video provided by Newsy
Powered by NewsLook.com
Sierra Leone in Lockdown to Control Ebola

Sierra Leone in Lockdown to Control Ebola

AP (Sep. 21, 2014) Sierra Leone residents remained in lockdown on Saturday as part of a massive effort to confine millions of people to their homes in a bid to stem the biggest Ebola outbreak in history. (Sept. 20) Video provided by AP
Powered by NewsLook.com
Sierra Leone's Nationwide Ebola Curfew Underway

Sierra Leone's Nationwide Ebola Curfew Underway

Newsy (Sep. 20, 2014) Sierra Leone is locked down as aid workers and volunteers look for new cases of Ebola. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins